Transcatheter measurement of mitral valve coaptation pressure: A proof-of-concept study using animal models

Mitral valve repair (MVr) is the preferred surgical treatment for primary mitral regurgitation; however, its success is limited by the lack of validated, accurate, and objective parameters for assessing the complete restoration of physiological mitral valve (MV) mechanics. Consequently, to address this challenge, intraoperative assessment of mitral valve coaptation pressure (MCP) has emerged as a promising approach. This study presents the first precise transcatheter measurement of MCP in animal hearts. Data were obtained using two custom-made force sensors: a 3Fr piezoresistive pressure catheter and a 15Fr flexible piezoelectric sensor. Experiments were conducted in both ex vivo (excised pig hearts activated by a pump) and in vivo (transseptal approach in a living pig) models. In a living pig with a healthy MV under normal hemodynamic conditions (peak systolic left ventricular pressure of 100 mmHg), the MCP ranged from 200 to 300 mmHg (25-40 kPa). Ex vivo experiments demonstrated that MCP was affected by transmitral pressure, mitral function changes (i.e., regurgitation), and MV morphology. These findings provide valuable insights into MV biomechanics and establish a solid foundation for developing medical devices to guide MVr procedures.